Elastic fluid power plant



1940- G. DIEDRICH 1 2,185,303

ELASTIC FLUID POWER PLANT Inventor:

I GUntheD Die TiCh, b Han/1 6 His Attorney Patented Jan. 2, 1940 Emsric FLUID POWER PLANT iintlier Diedrich, Berlin- Reinickendorf, Germany, assignor to General Electric Company, a

corporation of New York Application February 24, 1938, Serial No. 192,367

, In GermanyMarch' 12, 1937 4 Claims.

The present invention relates to elastic fluid power plants in which elastic fluid is produced in a forced circulation type boiler and conducted to a turbine or otherelastic fluid consumer. More specifically, the invention relates to the kind of power plants in which :the turbine or other consumer is subject to considerable variations in load. In such plants forced circulation type boilers have the advantage of low weight and quick regulation due to their low water or fluid content.

The object of my invention is to provide an improved arrangement of the kind of power plant above specified whereby the supply of air for maintaining combustion in, the boiler and the supply of feed water or like fluid are automatically controlled in response to changes of certain operating conditions.- v s For a consideration of what I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto in connection wtih the accompanying drawing.

The single figure of the, drawing illustrates a diagrammatic view of an elastic fluid power plant in accordance with my invention.

The arrangement comprises an elastic fluid generator or-boiler IU of the forced circulation type including a single flow heating element H and a burner 12. Fuel is conducted to the burner by a pipe 13 including a control valve i4, and air for maintaining combustion is supplied to the burner L2 through aconduit l5 connected to a compressor or blower IS; The elastic fluid produced in the boiler I is' conducted by a conduit ll'to the inlet of anelastic fluid turbine l8. The exhaust from the turbine I8 is condensed in a condenser l9 and the condensate formed in the latter is returned to and forced into the heating element l l of the boiler by means of a condensate pump 20 and a boiler feed .pump 2| connected in series with the latter. The boiler feed pump 20 has a discharge connected by a conduit 22 including a valve 23 to the inlet of the heating element II. The turbine has a shaft 24 for driving a propeller 25 through the intermediary of a gearing 26 and a coupling 21. Thepropeller 25 may also be connected to a combustion engine 28 by a clutch 29, the arrangement being such that the propeller may be driven by theturbine l8, or th engine 28 or both. r

The auxiliaries including the condensate pump 20, the boiler feed pump 2| and the blower or compressor IS in accordance with my invention are all driven by the turbine shaft 24, the condensate pump 20 being connected thereto through a gearing 30 and the feed pump 2| in the blower l6 having rotor elements directly connected to the turbine shaftz'i. In addition, all of the auxiliaries are of the centrifugal type and have preferably the same characteristics.

The valve 23 in the boiler feed line 22 is automatically controlled in response to changes of the elastic fluid temperature in the supply conduit I1 and changes of the pressure in the conduit 22 ahead of the valve 23 as regards the direction of flow of fluid through said conduit. The'.valve 23 may be of any suitable design having such a characteristic that it is moved to the opened position by the fluid under pressure flowing against the disk thereof and that for every pump speed, or pump-'butput pressure, it has a definite predetermined opened position. Such position, however, is adapted tobe modified in order to obtainthe proper regulation of the system, that is, to maintain a proper balance between the boiler output and the boiler feed liquid input. To this end the valve 23 has a stem 31 connected to the righthand and of a floating lever 32 which has an intermediate point 3.3 pivotallyconnected to a pressure-responsive device 34, in the present instance comprising a bellows 35 connected by a pipe 36 to the conduit 22. The left-hand end of the floating lever 32 is pivotally connected .to a temperature-responsive device 31 comprising a bellows 38 connected to a conduit 39 having a sealed end 40 disposed within the conduit l1.

During operation, the propeller speed may be -increased for the purpose of increasing its load by opening of the fuel valve l4 in the conduit I3 to increase theamount of fuel admitted to the burner l2 it being understood that an excess quantity of air is supplied by the blower It. This increases the amount of elastic fluid produced in the heating element II and raises the temperature and the pressure thereof whereby the elastic fluid turbine assumes a higher speed. The increased turbine speed in turn efiects an increased speed of the auxiliaries driven by the turbine, that is, of the condensate pump 20, the boiler feed pump 2| and the blower l6, thus increasing the discharge pressure of the auxiliaries. The temperature-responsive device 31 during increasing temperature of the live elastic fluid has the tendency to open the valve 23 and thereby to limit the rise of the temperature of the live elastic fluid to increased abputeight times so that a predeter- 66 mined rise in temperature of the elastic fluid, as indicated by the temperature responsive element 38, should be accompanied by a relatively large opening movement of the boiler feed valve 23. As the valve 23 is moved to a further opened position upon the expansion of the bellows member 38, the pressure ahead of the valve will drop by a predetermined amount which would ordinarily be followed by the immediate return of the valve disk toward its previous position of adjustment since it is primarily controlled by the force of the fluid flowing therethrough. According to the invention, however, the drop in pressure ahead of e the valve 23 upon an opening movement thereof is accompanied by a collapsing movement of the bellows member 35 which in effect removes a portion of the biasing force acting downwardly on the valve stem 3|. The valve 23 may thereby be stabilized at the more opened position. Conversely, assuming that the valve I4 is moved to a more closed position for decreasing the speed of the turbine 18, the generation of elastic fluid within the boiler I0 is decreased. The corresponding drop in temperature within the conduit I! results in the collapse of the bellows member 38 which tends to move the valve 23 to a more closed position. The pressure ahead of the valve 23 thereupon immediately builds up tending to force the disk thereof to the previous position of adjustment. The increase in pressure ahead of the valve 23, however, effects a loading of the stem 3| by the increase of pressure within the bellows member 35 bearing upon the floating lever 32 and the valve will be stabilized for the new load conditions.

Having described the methodat operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

What I claim as new and desire to obtain by Letters Patent of the United States is: 1

1. Elastic fluid power plant including the combination of a forced circulation type boiler having a discharge conduit and a burner, a centrifugal type blower for supplying compressed air to the burner, an elastic fluid turbine with a shaft and an inlet connected to the discharge conduit, a condenser for condensing exhaust fluid from the turbine, centrifugal type pumping means having an inlet conduit connected to the condenser and an outlet conduit with a valve connected to the boiler said blower and pumping means being mechanically driven from the turbine shaft, and means for automatically controlling said valve in response to temperature changes in the discharge conduit and pressure changes in the outlet conduit.

2. An elastic fluid power plant including the combination of an elastic fluid boiler, means for controlling the output of said boiler, an elastic fluid turbine connected to said boiler, a centrifugal type pump driven by said turbine for forcing feed liquid into said boiler, a conduit connecting said pump to said boiler, a valve in said conduit automatically adjustable in accordance with the pump delivery pressure, said valve being actuated in the opening direction upon increase in pump delivery pressure, means responsive to the temperature of the boiler output for regulating the opening of said valve, and means for modifying the regulation of said valve in response to the pressure ahead of said valve.

3. An elastic fluid power plant including the combination of an elastic fluid boiler, means for controlling the output of said boiler, an elastic fluid turbine connected to said boiler and adapted to be driven at a speed corresponding to said boiler output, a centrifugal type pump driven by said turbine for forcing feed liquid into said boiler, a conduit connecting said pump to said boiler, a valve in said conduit automatically adjustable in accordance with the pump delivery pressure, said valve being actuated in the opening direction upon increase in pump delivery pressure, means responsive to the temperature of the boiler output for regulating said valve, and means responsive to the output pressure of said pump for varying the regulation of said valve.

4. An elastic fluid power plant including the combination of an elastic fluid boiler, means for controlling the output of said boiler, an elastic fluid turbine connected to said boiler and adapted to be driven at a speed variable in accordance with saidboiler output, a centrifugal type pump driven by said turbine for forcing feed liquid into said boiler, a conduit including a valve connecting said pump to said boiler, said valve being automatically adjustable in the opened position in accordance with the delivery pressure of said pump, means for supplementally controlling said valve in accordance with the temperature of the boiler output, and means for modifying the supplemental control of said valve in accordance with the pressure ahead of said valve.

GUNTHER DIEDRICH. 

